Cellular telephone and microwave communication systems require relay stations to carry their signals beyond the range of a main transmitter. Each relay station includes a receiver to collect a signal, an amplifier to raise the power of the collected signal, a transmitter to send the amplified signal to its destination or to other relay stations, and antennas to receive and transmit the signals. Antennas for relay stations are usually permanently mounted on buildings or other permanent structures, but it is frequently necessary to install temporary relay stations to accommodate cellular telephone communication to areas that are remote from cities--for example, to geologic exploration sites, or to provide microwave transmission from sporting events or other events that are not performed in studios. The temporary relay stations also require antennas and those antennas must be mounted on masts in order to be at an adequate height. Temporary, mobile relay stations have been provided by mounting them on trailers or truck beds so that they may be transported on roads. At the site where a mobile relay station is to be used, a mast is mounted to hold the required antennas while the mechanisms necessary to deal with the communications are usually maintained on the vehicle that carries the equipment to the site where it is to be used.
The distance between transmitting antennas and receiving antennas is so critical that movement of an antenna caused by swaying of the mast on which it is mounted due to wind can seriously interfere with the ability of the relay station to function. Stabilizing the position of a mast-held antenna has been dealt with by using guy wires and massive foundations, but guy wires must be anchored at least fifty feet from the mast so that a ground area of about 300 square feet is required to provide a stable mast. The ground area for anchoring such guy wires is difficult to find in crowded urban environments, and it makes temporary relay stations unsightly and somewhat dangerous for pedestrians, bicyclists, and others using the area. In addition, massive foundations for temporary relay stations or for anchoring guy wires are unsightly and are difficult to remove without leaving permanent scars.